"The Vermont Senate blocked efforts by Entergy Corp. to win a 20-year license renewal for its Vermont Yankee nuclear power plant, an action that could encourage opponents of nuclear energy in other states.

The Senate vote, which was 26 to four, marks the first time a license renewal has been thwarted, and it sets the stage for the plant's closure by 2012, when the license expires.

The vote was striking because the state relies on the plant for a third of its electricity. In the past, license renewals have been routine, allowing energy companies to squeeze more life out of aging plants. To date, the NRC has renewed 59 reactor licenses, and 19 are pending.

The vote, which reflected fears about safety after leaks of radioactive tritium were discovered at the plant last year, is a blow to Entergy, which had planned to spin off six reactors, including Vermont Yankee, into the nation's first stand-alone nuclear power company, to be called Enexus Energy Corp."